Previously, if filtering subscriptions turned up no results, nothing was
printed. With this change, we explicitly print "no matching subscriptions"
instead.
Events always pass through these, adding to the stack trace on-crash.
This information is practically never useful, however. Adding !. leaves
these cores out of the traces.
Previously, the pretty-printing for %incoming and %outgoing results was hanging
on to and displaying irrelevant type information: "_list_ of subscriptions",
"wire with _head and tail_", and so on.
Here, we move to producing tangs, instead of vases, and print those. For the
%incoming and %outgoing cases, we print a line for every subscription, sorting
them by path and wire respectively, and giving clean, easily readable output.
+dbug [%state 'some-hoon'] now allows you to run some-hoon against the
application's state. That hoon has access to the bowl and stdlib for
more dbugging convenience.
